Offensive line play drives offensive performance, although some teams can overcome it and thrive anyway, like the AFC Champion Cincinnati Bengals. But Joe Burrow was sacked 70 times during the season and postseason, including 7 while losing the Super Bowl, so it's not surprising they're one of the teams doing the most in free agency.

It looks like a very strong draft class at offensive tackle, in which we might see a pair of top 5 picks and as many as 7 in the first round; good depth, too. So the teams that haven't yet done much along the line in free agency still have time to address holes. But here are the teams that seem to have done the most thus far this offseason.

Cincinnati: Getting franchise quarterback Burrow dropped 3.5 times per game isn't sustainable, so no surprise the team has moved aggressively in this regard. They could also pounce if one of the top linemen is available at No. 31 overall, but realizes that might not happen. So free agency has brough guard Alex Cappa (4 years, $40 million) likely center Ted Karras (3 years, $18 million) and right tackle La'el Collins (3 years, $30 million). Jonah Williams and Jackson Carman are the holdovers. The line couldn't possibly be worse, and should be a lot better.

Miami: It's a make-or-break year for Tua Tagovailoa, and the Dolphins look like they're trying to give him his best shot. Yesterday they signed Saints tackle Terron Armstead to a five-year, $75 million contract, and last week they added Cowboys guard Connor Williams with a two-year, $14 million deal. Tua was sacked just 20 times in 12 games last year, but a lot of that was due to offensive system (lots of short, quick passes that went nowhere); the pass protection was poor. A nice start to the offseason to give the passing game more of a chance.

Carolina: In general it's hard to be positive about what Carolina is doing. They've swung and missed at a couple of quarterbacks; it's easiest to assume at this point they're planning on drafting one of the top rookie quarterbacks, in a draft that doesn't have a Joe Burrow or Cam Newton who's going No. 1 overall. But the Panthers have at least brought in a couple of veterans for the line in former Ram Austin Corbett (3 years, $29 million) and center Bradley Bozeman (albeit to a cheap deal), and is reportedly in on still-unsigned Seahawks tackle Duane Brown. If they don't draft a quarterback in the top 10, seems likely they'll take one of the top offensive tackles.

Jacksonville: It got lost while the Jaguars were throwing mammoth contracts at pass catchers who didn't seem worthy of it, but they also added Washington guard Brandon Scherff (3 years, $50 million). That should be a big boon to Trevor Lawrence and whatever the team has available at running back, and the offense in general. They used the franchise tag to keep Cam Robinson around, and could potentially use the top pick in the draft on Alabama tackle Evan Neal (although defense seems more likely).

Pittsburgh: It's no secret the Steelers needed to upgrade their line, and did so with guard James Daniels (3 years, $27 million) and center Mason Cole (3 years, $16 million). Not big flashy signings, but help for a line that really needed it. They retained right tackle Chukwuma Okarafor (3 years, $29 million) who was one of the bright spots of last year's line. There's still work to do, which might come in the draft, but a step in the right direction.

Where there are winners, there must be losers. The Saints lost left tackle Armstead; that's a concern. The Bucs lost both of last year's starting guards (one in free agency, one to retirement); newcomer Shaq Mason will fill a spot, and they were also able to bring back center Ryan Jensen, but will likely be breaking in a youngster at the other guard spot. New England, San Francisco and Washington all seem to have lost more than they gained along the line. Plenty of time for these teams to address weaknesses, but those look like the big movers up and down so far.

--Andy Richardson